#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <RTClib.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

#define DHTPIN 2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

RTC_DS1307 rtc;

void setup() {
  lcd.begin(16, 2);
  lcd.backlight();
  
  dht.begin();
  
  if (!rtc.begin()) {
    lcd.print("RTC fail");
    while (1);
  }
  
  if (!rtc.isrunning()) {
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
  
  lcd.setCursor(0, 0);
  lcd.print("Digital Clock");
  lcd.setCursor(0, 1);
  lcd.print("with Thermometer");
  delay(2000);
}

void loop() {
  DateTime now = rtc.now();
  
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();
  
  if (isnan(temperature) || isnan(humidity)) {
    lcd.clear();
    lcd.print("Reading error");
    lcd.setCursor(0, 1);
    lcd.print("temp/humi");
    delay(2000);
    return;
  }
  
  lcd.clear();
  lcd.setCursor(0, 0);
  if (now.hour() < 10) lcd.print("0");
  lcd.print(now.hour(), DEC);
  lcd.print(":");
  if (now.minute() < 10) lcd.print("0");
  lcd.print(now.minute(), DEC);
  lcd.print(":");
  if (now.second() < 10) lcd.print("0");
  lcd.print(now.second(), DEC);
  
  lcd.print(" T:");
  lcd.print((int)temperature);
  lcd.print("C");
  
  lcd.setCursor(0, 1);
  if (now.day() < 10) lcd.print("0");
  lcd.print(now.day(), DEC);
  lcd.print("/");
  if (now.month() < 10) lcd.print("0");
  lcd.print(now.month(), DEC);
  lcd.print("/");
  lcd.print(now.year() % 100, DEC);
  
  lcd.print(" H:");
  lcd.print((int)humidity);
  lcd.print("%");
  
  delay(1000);
}